As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EMERGENCY BATTERY PACKS M1669; M1670; M1672; AND M1674 FAILED CAPACITY TEST.<[01] REMOVED AND REPLACED EMERGENCY BATTERY PACK AT LOCATIONS M1669/M1670/M1672 AND M1674 IN REF WITH B737 AMM 33-51-06-960-805.EMERGENCY BATTERY PACK INSTALLATION TEST NORMAL.;[02] CERTIFIED WORK STEPS FOR BATTERY PACK REPLACEMENT.